powerpc/configs/6xx: Drop no longer needed CONFIG_NETFILTER_XT_MATCH_SOCKET

Since commit 8db4c5be ("netfilter: move socket lookup
infrastructure to nf_socket_ipv{4,6}.c") we no longer need to set
CONFIG_NETFILTER_XT_MATCH_SOCKET in our defconfigs.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/configs/ppc6xx_defconfig

@@ -185,7 +185,6 @@ CONFIG_NETFILTER_XT_MATCH_QUOTA=m
 CONFIG_NETFILTER_XT_MATCH_RATEEST=m
 CONFIG_NETFILTER_XT_MATCH_REALM=m
 CONFIG_NETFILTER_XT_MATCH_RECENT=m
-CONFIG_NETFILTER_XT_MATCH_SOCKET=m
 CONFIG_NETFILTER_XT_MATCH_STATE=m
 CONFIG_NETFILTER_XT_MATCH_STATISTIC=m
 CONFIG_NETFILTER_XT_MATCH_STRING=m